Properties of thermoplastic blends: starch–polycaprolactone

• Published in: Polymer (Guilford) Vol. 41; no. 11; pp. 4157 - 4167
• Main Authors: Averous, L., Moro, L., Dole, P., Fringant, C.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-05-2000; Elsevier
• Subjects: Applied sciences; Blend; Exact sciences and technology; Natural polymers; Physicochemistry of polymers; Polycaprolactone; Starch and polysaccharides; Thermoplastic starch; Blend; Polycaprolactone; Thermoplastic starch; Polymer blends; Thermoplastics; Property composition relationship; Thermal transition; Mechanical properties; Experimental study; Wettability; Plasticizer; Dynamic mechanical properties; Concentration effect; Surface properties; Oside polymer; Wheat starch
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(99)00636-9

Different compositions of wheat thermoplastic starch (TPS) and polycaprolactone (PCL) are melt blended by extrusion and injected. Different properties are determined: mechanical properties (tensile and impact tests), thermal and thermomechanical properties (DSC and DMTA) and hydrophobicity (contact angle measurement). A large range of blends is analysed with different glycerol (plasticizer):starch contents ratios (0.14:0.54) and various PCL concentrations (up to 40
wt.%). From the behaviour of each polymeric system, it is possible to analyse the relationship properties of each component proportion on the blends. The ageing of the system is studied and shows a structural evolution of the material after injection during several weeks. We have noticed a fairly low compatibility between both polymeric systems. Finally, the addition of PCL to TPS matrix allows to overcome the weakness of pure TPS: low resilience, high moisture sensitivity and high shrinkage, even at low PCL concentration, e.g. 10
wt.%.